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Biomedical subjects

E Koch

Publications and source records attributed to E Koch.

133 records · Page 8Linked to original sources
PubMedDate not supplied

Flow cytometric evaluation of the effects of doxorubicin on rat spermatogenesis.

Histopathologic examination of testicular tissue allows testicular impairment to be investigated. As an alternative to histopathology, flow cytometry (FCM) using a triple staining technique that combines DNA-ploidy with mitochondria stainability and vimentin immunostaining has also been utilized to evaluate testicular damage. In this article we evaluate the effects on spermatogenesis after acute exposure of rats to doxorubicin. Testicular cell suspensions of treated and control animals were analyzed by FCM. This allows several cell types to be identified and quantified, giving a control pattern. Deviations from this control pattern are considered as an indication of testicular damage. Doxorubicin produced a depletion of spermatogonia as early as 3 d after treatment. This effect could be followed through the temporal evolution of spermatogenesis. Comparable results were obtained by histopathology. The presented results show that FCM is a suitable and sensitive method for the detection of testicular damage. The advantages of FCM over other techniques include its rapidity and objectivity.

Animals↗
PubMedDate not supplied

New and traditional approaches for the assessment of testicular toxicity.

In this study, the suitability of several methods for the assessment of testicular damage, including histopathology, flow cytometry (FCM), testicular sperm head counts, and secretion of androgen binding protein (ABP), has been evaluated. Testicular toxicity after acute exposure of adult rats to different doses of the known toxicant 1,3-dinitrobenzene (DNB) was analyzed. The effects showed dose dependence, in spite of the large variability within each dose group. Histopathology and FCM showed germ cell depletion, particularly of round spermatids; testicular sperm head counts were reduced and ABP production was increased. All evaluated methods showed similar sensitivities. The increased testicular ABP levels support the theory that the Sertoli cell is the likely target of DNB induced testicular toxicity, producing subsequent germ cell depletion. The presented results show the suitability of FCM for the analysis of testicular damage and also support the usefulness of including a metabolic marker for Sertoli cell function.

Androgen-Binding Protein↗
PubMedDate not supplied

Early detection of psychotic disorders in adolescents: specificity of basic symptoms in psychiatric patient samples.

Based on the results of adult studies that have shown a subgroup of basic symptoms to have a predictive value for later schizophrenic disorder, a cross-sectional study on 36 schizophrenic and 75 nonschizophrenic adolescent psychiatric inpatients was performed to elucidate the specificity of prodromal signs in early age groups. The occurrence of any single basic symptom does not show schizophrenic specificity in adolescents, but the number of basic symptoms in the categories of the Bonn Scale for the Assessment of Basic Symptoms is increased in schizophrenic patients compared with subjects with other diagnoses. The interrelation between minus symptoms and cognitive symptoms exerts a higher amount of cognitive disturbances given a certain level of irritation in schizophrenic adolescents. With the help of odds ratios, the seven most discriminating cognitive items could be elucidated including perception, information processing and action tendency.

Adolescent↗
PubMedDate not supplied

Water pollution and diseases in fish (an epizootiologic survey).

Three watersheds, varying from highly polluted or moderately polluted to essentially pollution-free, were surveyed to determine the frequency of fish disease. Over a five year period, it was found that a relationship existed between the level of pollution and frequency of disease. The occurrence rates of microbial and oncogenic diseases increased similarly in relation to increases in pollution in the waters. Since the water systems studied provide recreational opportunities for man, it is suggested that catching and subsequent ingesting of diseased fish from these waters present a health hazard.

Animals↗
PubMedDate not supplied

The course of aversive conditioning related to the excretion of catecholamines, DOPA and their oxidoreduction states.

Excretion of catecholamines, DOPA and their oxidoreduction states were studied during aversive conditioning in a 10-sitting experiment in man. Urinary samples in 3 intervals of 8 h. before respective sitting and 20, 80 and 200 minutes after the sitting. The initial unspecific phase of conditioning corresponds to an increase and decrease of catecholamine elimination characterized by a prevailing of adrenaline and noradrenaline (interpreted as the same change in level of unconditioned excitability). In the specific phase of conditioning more important participation of dopamine and probably DOPA and their metabolites were observed. The anticipatory conditioned reflex itself (manifested in urinary samples before resp. sittings) is characterized by surplus of adrenaline and noradrenaline. The results support our conception of two phases in conditioning (and generally learning) process.

Avoidance Learning↗